… we show that the class of ecological systems that will exhibit leading indicators of regime shifts is limited, and that there is a set of ecological models and, therefore, also likely to be a class of natural systems for which there will be no forewarning of a regime change … We then illustrate the impact of these general arguments by numerically examining the dynamics of several model ecological systems under slowly changing conditions. Our results offer a cautionary note about the generality of forecasting sudden changes in ecosystems.

On Friday, the world’s most successful businessperson and most powerful philanthropist did something outstandingly bold, that went almost unremarked: Bill Gates announced that his top priority is getting the world to zero climate emissions.

“Engineering without engines. We should use contemporary technology and computation capacity to make our buildings independent of machinery. Building services today are essentially mechanical compensations for the fact that buildings are bad for what they are designed for—human life. Therefore we pump air around, illuminate dark spaces with electric lights, and heat and cool the spaces in order to make them livable. The result is boring boxes with big energy bills. If we moved the qualities out of the machine room and back into architecture’s inherent attributes, we’d make more interesting buildings and more sustainable cities.”

These are all ideas very much at the core of green building, but there’s a focus here that I think is important: that sustainable cities involve removing machines designed to do ecologically stupid things, and that new technology should reorient the city around the human body.

Last year Project for Public Spaces and I published the Great Neighborhood Book, which offers hundreds of ideas from around the world about making community improvements on issues ranging from crime prevention to environmental restoration. Since then almost everyone I meet asks: What’s your favorite neighborhood?

Looking at data from more than 40,000 mortgages throughout Chicago, San Francisco and Jacksonville, Fla., the researchers behind the Location Efficiency and Mortgage Default report found that the rate of mortgage foreclosure actually decreased in neighborhoods that were more compact, walkable and connected to public transportation (after accounting for important factors like income).

Without directing future development toward walkable urbanism, the climate impacts of sprawl will overwhelm other efforts to curb greenhouse gas emissions, said Robert Cervero, a professor specializing in transportation and land use policy at UC Berkeley. “Urban development patterns have a significant role to play in carbon reduction,” Cervero told the audience. “Otherwise we’ll just get knocked back by land-use patterns. Sustainable urbanism has to be part of the equation.”

Cervero attached some rough numbers to these “embedded energy savings.” While transit investment alone can achieve a 10 to 20 percent reduction in America’s per capita greenhouse gas emissions, he said, factoring in the embedded energy savings of walkable development boosts that figure to 30 percent. That’s 30 percent compared to present-day emissions levels. The reduction could reach as high as 60 percent, Cervero added, compared to the level of per-capita emissions that would result from continuing business-as-usual sprawl-inducing policies.

Walkability is clearly critical to bright green cities. You can’t advocate for car-free or car-sharing lives if people need cars to get around, and the enticement to walk is key to making density wonderful, to providing realistic transit options, to making smaller greener homes compelling and to growing the kind of digitally-suffused walksheds that post-ownership ideas seem to demand. So knowing how to define “walkable” is important.

…The big thing I think falls out of most walkability formulas is a quality critical to the actual experience of walkability, and that’s the extent to which the place in which you live is connected (by walking routes and easy transit) to other places worth walking to.

…The true test of walkability I think is this: Can you spend a pleasant half hour walking or on transit and end up at a variety of great places? The quality of having a feast of options available when you walk out your front door is what I starting to think of as “deep walkability.”

It’s this deep walkability that ought to be the top priority driving urban design and development in our communities. We ought to be looking at how to knit our walkable communities together and how to make friendlier the unwalkable streets between them.

In most cities, serious walkers (and bikers) share stories about the routes they’ve taken, hidden paths through the fractured landscape that let you walk safely and happily from one people-centered place to another. A killer urban ap would be one that revealed these urban songlines. A smart urban policy would be one that aimed to weave new walking routes through the whole urban fabric, until places walkers feared to tread were the exception rather than the expectation.

Alex also points to a New York Times article Street Corners vs. Cul de Sacs that the property values of walkable neighbourhoods have been more resilience to the bursting of the US property bubble.

A study published in August by C.E.O.’s for Cities, a group of urban redevelopment advocates, found that in many ways, the street corner beats the cul de sac. It looked at the sales of 90,000 homes in 15 markets to estimate how much value was associated with something called the Walk Score. Using a 100-point scale, this score rates the number of destinations, including libraries, parks and coffee shops, within walking distance of a home.

…The study found that houses with above-average Walk Scores commanded a premium. It was as much as $30,000 in cities like Charlotte, N.C., Chicago, Sacramento and San Francisco, wrote Joe Cortright, the study’s author and an economist at Impresa, a consulting firm in Portland, Ore.

Pedreres de s’Hostal is a disused stone quarry on the island of Minorca, Spain. In 1994, the quarry saw its last stonecutters, and since then, the non-profit organization Líthica has been hard at work transforming this industrial landscape into a post-industrial heritage park.

Based on climate models and a survey of suitable habitats, scientists introduced 500 to 600 individuals of twobutterfly species to new sites in England, miles away from what were, in 1999 and 2000, the northern limits of their natural ranges. After monitoring for six years, they found that both introduced populations grew and expanded their turf from the point of release, similarly to newly colonized natural areas.

The butterflies’ success outside of their usual limits suggests that their naturally shifting distributions had been lagging behind the pace of climate warming, the researchers conclude. The results also bode well for the careful use of this sometimes controversial technique for other species threatened by climate change. After all, wildlife can only run so fast and for those species moving up mountains to escape the heat, there’s only so far they can go.

MacArthur Foundation granting $2 million to help ecosystems and human communities adapt to the effects of climate change. On Gristmill:

the IUCN and the World Wildlife Fund — will use it to establish a new Ecosystems and Livelihoods Adaptation Network. Details on the network are still being hashed out, but it’s intended to be a resource for promoting best practices to conservation groups, governments, and others. It will aid projects such as creating protected corridors to help mountain-dwelling animals migrate to higher elevations and restoring natural barriers on coastlines, such as mangrove forests.

If we start to see faster-than-expected increases in temperature, deadly heat waves and storms, crop failures and drought, the pressure to do something will be enormous. Desperation is a powerful driver. Desperation plus a (relatively) low-cost response, coupled with quick (if not necessarily dependable) benefits, can become an unstoppable force.

If we don’t want to see geoengineering deployed, we have to get our carbon emissions down as rapidly and as widely as possible. If we don’t — if our best efforts aren’t enough against decades of carbon growth and temperature inertia — we will see efforts to do something, anything, to avoid global catastrophe.

Many of us oppose geoengineering megaprojects, not because we are afraid of science or technology (indeed, most bright green environmentalists believe you can’t win this fight without much more science and technology), but because these kinds of megaprojects are bad planetary management.

It’s bad planetary management to take big chances with a high probability of “epic fail” outcomes (like emptying the sea of life through ocean acidification). It’s bad planetary management to build large, singular and brittle projects when small, multiple and resilient answers exist and will suffice if employed. It’s bad planetary management to assume that this time — unlike essentially every other large-scale intervention in natural systems in recorded history — we’ll get it right and pull it off without unintended consequences.

Jamais and Alex debate their points a bit in the WorldChanging comments.

If the nature of even non-catastrophic climate change is to make the world much more unpredictable, adaptation is impossible in a meaningful sense.What is possible is planned resilience: we can make our own systems more rugged and distributed, our natural systems protected and managed in ways that best preserve their ability to respond to (and incorporate) disturbance while preserving ecosystem services and biodiversity. We can plan to become good at dealing with chaos. But that is quite different than adapting to a singular change, and it takes dramatically different kinds of priorities.

Now, “Resilience!” is not exactly be the battle-cry we’re looking for. Anyone else got a suggest about how we might compellingly describe the goal here?